hbase-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Ted Yu (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HBASE-14268) Improve KeyLocker
Date Thu, 20 Aug 2015 16:17:46 GMT

    [ https://issues.apache.org/jira/browse/HBASE-14268?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14705199#comment-14705199
] 

Ted Yu commented on HBASE-14268:
--------------------------------

{code}
117	    ReentrantLock lock = getLock(key);
118	    purge();
{code}
Do we need to call purge() for every acquireLock() ?

> Improve KeyLocker
> -----------------
>
>                 Key: HBASE-14268
>                 URL: https://issues.apache.org/jira/browse/HBASE-14268
>             Project: HBase
>          Issue Type: Improvement
>          Components: util
>            Reporter: Hiroshi Ikeda
>            Assignee: Hiroshi Ikeda
>            Priority: Minor
>         Attachments: HBASE-14268.patch, KeyLockerPerformance.java
>
>
> 1. In the implementation of {{KeyLocker}} it uses atomic variables inside a synchronized
block, which doesn't make sense. Moreover, logic inside the synchronized block is not trivial
so that it makes less performance in heavy multi-threaded environment.
> 2. {{KeyLocker}} gives an instance of {{RentrantLock}} which is already locked, but it
doesn't follow the contract of {{ReentrantLock}} because you are not allowed to freely invoke
lock/unlock methods under that contract. That introduces a potential risk; Whenever you see
a variable of the type {{RentrantLock}}, you should pay attention to what the included instance
is coming from.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Mime
View raw message